1. Field of the Invention
The invention relates to a heat and sound insulating panel intended particularly for the dry insulation of under-roof spaces, or for making up suspended ceilings particularly for industrial buildings or buildings intended for public use, such as business premises, concert halls, theatres, etc.
2. Background of the Prior Art
A heat and sound insulating panel normally consists of a basic layer of mineral fibers, for example glass fibers, provided on the visible surface side with a surfacing layer which gives it a decorative finished appearance. This surfacing layer is for example a film of polyvinyl chloride, or a sheet of glass fibers obtained preferably by the wet method or a film of aluminum possibly backed with kraft paper.
From the point of view of decorative appearance, glass sheet surfaces are markedly superior to those of other materials because they can be painted and blend in with the decor. But these glass sheet surfacings have the serious drawback of being permeable to air and to steam. Behind such a panel--for example in the spaced comprised between the ceiling slab of the floor above and the suspended ceiling--ambient pressure is generally different from that which is obtained in the room. Consequently, there is an exchange of gases through the panel consisting of two porous layers which become veritable dust filters and the panels quickly become blackened.
Impermeable surfacings of the aluminum film type cannot be painted and are therefore more especially suitable for factory sheds where the finished appearance is of less importance. Furthermore, they at least partly reflect the sound waves which therefore cannot be deadened by the basic layer of glass fibers. Sound insulation is therefore considerably lessened.
The object of the present invention is a heat and sound insulating panel which combines good aesthetic quality with good heat and sound insulating performance and simple maintenance.